Method for extracting total flavonoid components in cinnamomum camphora leaves based on ultrasonic method

Abstract

The invention belongs to the technical field of traditional Chinese medicine effective component extraction, and particularly relates to a method for extracting total flavonoid components in cinnamomum camphora leaves based on an ultrasonic method. The method for extracting the cinnamomum camphora leaf total flavonoids based on the ultrasonic method has remarkable advantages. The extraction efficiency of an ultrasonic method is higher than that of a microwave method, the extraction rate and production efficiency can be greatly improved, and industrial large-scale production requirements are met; the low-temperature extraction environment avoids degradation of flavone active components, fully retains antioxidant, anti-inflammatory and other biological activities, and ensures the quality of the extract. Meanwhile, the method is short in time consumption and small in solvent dosage, energy consumption and cost are reduced, organic solvent emission is reduced, and the method conforms to the green production concept; according to the method, a response surface method and Box-Behnken design optimization process are combined, repeatability and stability are good, a reliable scheme is provided for standardized extraction of the cinnamomum camphora leaf total flavonoids, and efficient development of cinnamomum camphora resources is promoted.

Description

Technical Field

[0001] The invention belongs to the technical field of extraction of effective components of traditional Chinese medicines, and particularly relates to a method for extracting total flavonoid components from camphor trees leaves based on an ultrasonic method. Background Art

[0002] Flavonoids are a class of natural active ingredients widely found in plants. They possess numerous biological activities, including antioxidant, anti-inflammatory, and antibacterial activities, and have great potential for application in medicine, food, and cosmetics. Camphora (Camphora officinarum), a traditional medicinal plant with a long history, contains flavonoids with diverse biological activities, including antioxidant, anti-inflammatory, and antibacterial activities, demonstrating significant potential for application in these areas. However, current extraction processes for flavonoids from Camphora leaves still suffer from significant drawbacks. Traditional methods, such as reflux and Soxhlet extraction, not only suffer from long extraction cycles and high solvent consumption, but also suffer from high-temperature extraction processes that can easily lead to degradation of the flavonoid active ingredients, compromising extract quality and yield. With the development of green extraction technologies, ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE), with their advantages of high efficiency, energy conservation, and low-temperature operation, have become cutting-edge research in natural product extraction. These new technologies enable efficient dissolution of target components in a short time, effectively minimizing the destruction of active ingredients. These new technologies offer new research directions for the extraction of flavonoids from Camphora leaves, but further exploration of their optimal process parameters is urgently needed.

[0003] Currently, research on optimizing the extraction process of flavonoids from Cinnamomum camphora leaves has largely focused on single extraction techniques or simple parameter screening, lacking a systematic analysis of multifactor interactions. While single-factor experiments can initially determine the range of key parameters, they struggle to reveal nonlinear relationships between complex variables. Response surface methodology (RSM), by establishing mathematical models, can efficiently optimize process conditions and predict optimal extraction results, demonstrating significant advantages in the field of natural product extraction. Furthermore, the differences in the mechanisms of action between ultrasound and microwave techniques may have different effects on flavonoid yield and component stability, but comparative studies are still limited. Therefore, it is necessary to utilize response surface methodology to optimize the extraction process of flavonoids from Cinnamomum camphora leaves. Summary of the Invention

[0004] In order to overcome the deficiencies of the above-mentioned prior art, the present invention uses Cinnamomum camphora leaves as raw materials, adopts ultrasound-assisted extraction and microwave-assisted extraction techniques respectively, combines single-factor experiments with Box-Behnken response surface design, systematically optimizes extraction process parameters, clarifies the influence of variables such as ethanol concentration, material-liquid ratio, extraction time, and ultrasonic power (or microwave power) on flavonoid yield, and compares the extraction efficiency and applicability of the two methods, in order to provide an efficient extraction route for the green and efficient extraction and industrial development of flavonoid components from Cinnamomum camphora leaves.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] The invention provides a method for extracting total flavonoid components from camphor tree leaves based on an ultrasonic method. Specifically, the method comprises the following steps: adding camphor tree leaf dry powder to an ethanol solution with a volume concentration of 50-70% at a solid-liquid ratio of 1 g:24-32 mL; then placing the powder in an ultrasonic instrument and performing ultrasonic extraction for 30-40 minutes at an ultrasonic power of 220-270 W; and after extraction, removing solid impurities and collecting a filtrate to obtain the flavonoid components.

[0007] As one of the preferred embodiments of the present invention, the material-liquid ratio is 1 g:32 mL.

[0008] As one of the preferred embodiments of the present invention, the volume concentration of the ethanol solution is 50%.

[0009] As one of the preferred solutions of the present invention, the ultrasonic power of ultrasonic extraction is 280W.

[0010] As one of the preferred embodiments of the present invention, the ultrasonic extraction time is 30 minutes.

[0011] The present invention optimizes the extraction process of total flavonoids from Cinnamomum camphora leaves using ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) techniques, combined with response surface methodology (RSM). A Box-Behnken design was used to establish process models for the two methods, and the extraction efficiencies were compared and analyzed. First, single-factor experiments were conducted to optimize the design of four factors: ethanol concentration, solid-liquid ratio, power, and extraction time, and the effects of these factors on extraction efficiency were investigated. The results showed that the optimal ultrasonic extraction conditions for total flavonoids from Cinnamomum camphora leaves were as follows: extraction time 30 minutes, solid-liquid ratio 1:32 (g / mL), ethanol concentration 50%, and ultrasonic power 280W. Under these conditions, the total flavonoid yield reached 8.979%. The optimal microwave extraction conditions for total flavonoids from Cinnamomum camphora leaves were as follows: extraction time 18 minutes, solid-liquid ratio 1:23 (g / mL), ethanol concentration 57%, and microwave power 543W. Under these conditions, the total flavonoid yield reached 7.375%. It can be seen that the extraction rate of ultrasonic method is higher than that of microwave method, and the total flavonoids content reaches 0.0449 mg / mL. The above results provide a reference for the efficient extraction of Cinnamomum camphora leaves.

[0012] As one preferred embodiment of the present invention, the camphor leaf dry powder is camphor leaf residue dry powder. Extracting flavonoids from camphor leaf residue dry powder can turn waste into treasure, achieve high-value resource utilization, and improve industrial efficiency; reduce raw material costs, facilitate large-scale production, and reduce waste disposal pressure, practicing environmental protection. Furthermore, the leaf residue dry powder is easy to store and transport and has high stability, ensuring the continuity and supply stability of flavonoid extraction production.

[0013] As one of the preferred embodiments of the present invention, the size of the camphor leaf powder is 50-100 mesh. This size of camphor leaf powder can increase the contact area with the solvent, improve extraction efficiency, reduce impurity dissolution, facilitate subsequent processing, and meet the needs of industrial production.

[0014] As one of the preferred embodiments of the present invention, a drying step is further included after collecting the filtrate.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The present invention is based on the method of extracting total flavonoids from camphor tree leaves by ultrasonic method, which has significant advantages. First, the ultrasonic method has higher extraction efficiency than the microwave method, which can significantly improve the extraction rate of total flavonoids from camphor tree leaves, greatly improve production efficiency, and meet the output requirements of industrial large-scale production; secondly, the ultrasonic-assisted extraction process is carried out at low temperature, which effectively avoids the destruction of flavonoid active ingredients by high temperature, retains its antioxidant, anti-inflammatory, antibacterial and other biological activities to the greatest extent, and ensures the quality of the extract; thirdly, the extraction method takes a short time and consumes less solvent, which not only reduces energy consumption and production costs, but also reduces the use and emission of organic solvents, which is in line with the concept of green environmental protection; in addition, the extraction process optimized by combining the response surface method and Box-Behnken design has good repeatability and stability, and provides a reliable solution for the standardized and normalized extraction of total flavonoids from camphor tree leaves, which helps the efficient development and utilization of camphor tree resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is the standard curve of rutin concentration and absorbance;

[0018] Figure 2 The effect of ultrasonic extraction time on the yield of total flavonoids from Cinnamomum camphora leaves;

[0019] Figure 3 The effect of ultrasonic power on the yield of total flavonoids from Cinnamomum camphora leaves;

[0020] Figure 4 The effect of ethanol concentration on the yield of total flavonoids from Cinnamomum camphora leaves during ultrasonic extraction;

[0021] Figure 5 The effect of the solid-liquid ratio on the yield of total flavonoids from Cinnamomum camphora leaves during ultrasonic extraction;

[0022] Figure 6 The effect of microwave extraction time on the yield of total flavonoids from Cinnamomum camphora leaves;

[0023] Figure 7 The effect of microwave power on the yield of total flavonoids from Cinnamomum camphora leaves;

[0024] Figure 8 The effect of ethanol concentration on the yield of total flavonoids from Cinnamomum camphora leaves during microwave extraction;

[0025] Figure 9 Effect of the solid-liquid ratio in microwave extraction on the yield of total flavonoids from Cinnamomum camphora leaves;

[0026] Figure 10 The effect of the interaction between ultrasonic power and ultrasonic time on the yield of flavonoids;

[0027] Figure 11 The effect of the interaction between ultrasonic power and material-liquid ratio on the yield of flavonoids;

[0028] Figure 12 The effect of the interaction between ultrasonic power and ethanol concentration on the yield of flavonoids;

[0029] Figure 13 The effect of the interaction between ultrasonic time and material-liquid ratio on the yield of flavonoids;

[0030] Figure 14 The effect of the interaction between ultrasound time and ethanol concentration on the yield of flavonoids;

[0031] Figure 15 The effect of the interaction between solid-liquid ratio and ethanol concentration on flavonoid yield;

[0032] Figure 16 The effect of the interaction between ethanol concentration and microwave power on the yield of flavonoids;

[0033] Figure 17 The effect of the interaction between ethanol concentration and microwave time on the yield of flavonoids;

[0034] Figure 18 The effect of the interaction between ethanol concentration and solid-liquid ratio on flavonoid yield;

[0035] Figure 19 The effect of the interaction between microwave power and microwave time on the yield of flavonoids;

[0036] Figure 20 The effect of the interaction between microwave power and material-liquid ratio on the yield of flavonoids;

[0037] Figure 21 This is the effect of the interaction between microwave time and material-liquid ratio on the yield of flavonoids. DETAILED DESCRIPTION

[0038] The following is a further description of specific embodiments of the present invention. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0039] The experimental methods in the following examples are conventional methods unless otherwise specified, and the experimental materials used in the following examples are commercially available unless otherwise specified.

[0040] Example: Optimization of flavonoid extraction process from borneol camphor leaves using response surface methodology

[0041] 1 Materials and Methods

[0042] 1.1 Experimental instruments and materials

[0043] The instruments and materials used in the experiment are shown in Tables 1 and 2.

[0044] Table 1 Experimental instruments

[0045]

[0046]

[0047] Table 2 Experimental reagents

[0048]

[0049] 1.2 Experimental methods

[0050] 1.2.1 Extraction and determination of total flavonoids in Cinnamomum camphora leaves

[0051] 1.2.1.1 Determination of flavonoids:

[0052] This experiment used an aluminum nitrate colorimetric method to determine the total flavonoid content of Cinnamomum camphora leaves. The specific method is as follows: 0.5g of dry powder (80 mesh) of Cinnamomum camphora leaf residue was weighed, a certain amount of solvent was added, and then the mixture was extracted using an ultrasonic or microwave apparatus. Solid impurities were removed by suction filtration, and the filtrate was collected. The resulting filtrate was placed in a 100mL volumetric flask and brought to volume. 1mL of the filtrate was added to a 10.0mL stoppered test tube. 0.5mL of 5% sodium nitrite solution was added to the flask and the mixture was allowed to stand for 6 minutes; 0.5mL of 10% aluminum nitrate solution was then added and the mixture was allowed to stand for 6 minutes; 4.0mL of 4% sodium hydroxide solution was added and the mixture was allowed to stand for 15 minutes; and finally, the corresponding solvent was added to bring the volume to the mark. A blank control was performed using the corresponding solvent instead of the sample solution, and the absorbance was measured at a wavelength of 510nm. Samples extracted under different conditions were simultaneously taken and the absorbance was measured. The flavonoid concentration in the extract was calculated based on the standard curve.

[0053] The calculation formula of the extraction yield Y of total flavonoids is:

[0054] Where: V-volume of the extract, mL; C-concentration of flavonoids in the test solution, mg / mL; m-mass of dry powder of Cinnamomum camphora leaf residue, g.

[0055] 1.2.1.2 Preparation of standard curve

[0056] Accurately weigh 7 mg of rutin standard and place it in a 50 mL volumetric flask, add 70% ethanol solution to dissolve it, dilute to the mark, shake well, and obtain 0.14 mg / mL of rutin standard stock solution. Accurately aspirate 0.0 mL, 1.0 mL, 2.0 mL, 3.0 mL, 4.0 mL, and 5.0 mL of rutin standard stock solution respectively and place them in a series of 10 mL volumetric flasks. Then, add 0.5 mL of 5% sodium nitrite solution to each of the above volumetric flasks, shake well, and let it stand for 6 minutes; then add 0.5 mL of 10% aluminum nitrate solution, shake well, and let it stand for 6 minutes; then add 4 mL of 4% sodium hydroxide solution, dilute to the mark with solvent, shake well, and measure the absorbance at 510 nm. The standard curve is shown in the figure below. Figure 1 shown.

[0057] like Figure 1 As shown, the rutin standard solution has a good linear relationship in the range of 0.014-0.07 mg / mL: y=8.6757x+0.0015, R 2 =0.9995.

[0058] 1.2.2 Single-factor experiment

[0059] 1.2.2.1 Ultrasonic method

[0060] (1) Extraction time: Weigh 0.5 g of Cinnamomum camphora, fix the ultrasonic power to 60 W, the ethanol concentration to 60%, and the solid-liquid ratio (g / mL) to 1:24. Ultrasonic times were set to 10 min, 20 min, 30 min, 40 min, and 50 min, respectively, to extract the active ingredients. Each group was measured three times to obtain five sets of data, and a graph was drawn to obtain the optimal ultrasonic time level range.

[0061] (2) Ultrasonic power: Weigh 0.5 g of Cinnamomum camphora, fix the ultrasonic time at 40 min, the ethanol concentration at 60%, and the solid-liquid ratio at 1:24. Ultrasonic powers of 160 W, 200 W, 240 W, 280 W, and 320 W were used to extract the active ingredients. Each group was measured three times to obtain five sets of data, and a graph was drawn to obtain the optimal ultrasonic power level range.

[0062] (3) Ethanol concentration: Weigh 0.5 g of Cinnamomum camphora, set the ultrasonic power to 60 W, the ultrasonic time to 40 min, and the material-liquid ratio to 1:24, and extract the active ingredients at 40%, 50%, 60%, 70%, and 80% ethanol concentrations. Repeat the measurement three times for each group to obtain five sets of data, and then draw a graph to obtain the optimal ethanol concentration level range.

[0063] (4) Material-liquid ratio: Weigh 0.5 g of Cinnamomum camphora, fix the ultrasonic time at 40 min, the ultrasonic power at 240 W, and the ethanol concentration at 60%, and take the material-liquid ratios of 1:16, 1:20, 1:24, 1:28, and 1:32 respectively to extract the active ingredients. Repeat the measurement three times for each group to obtain five sets of data, and draw a graph to obtain the optimal material-liquid ratio level range.

[0064] 1.2.2.2 Microwave method

[0065] (1) Extraction time: Weigh 0.5 g of Cinnamomum camphora, fix the microwave power to 500 W, the ethanol concentration to 60%, and the solid-liquid ratio (g / mL) to 1:20, and take ultrasonic time of 4 min, 8 min, 12 min, 16 min, and 20 min respectively to extract the active ingredients. Each group was measured three times to obtain five sets of data, and a graph was drawn to obtain the optimal microwave extraction time level range.

[0066] (2) Microwave power: Weigh 0.5 g of Cinnamomum camphora, fix the microwave time at 12 min, the ethanol concentration at 60%, and the solid-liquid ratio at 1:20. The effective components were extracted at microwave powers of 300 W, 400 W, 500 W, 600 W, and 700 W, respectively. Each group was measured three times, and five sets of data were obtained. The optimal microwave power level range was obtained by plotting the data.

[0067] (3) Ethanol concentration: Weigh 0.5 g of Cinnamomum camphora, fix the microwave temperature at 60°C, the microwave time at 12 min, and the solid-liquid ratio at 1:20, and extract the active ingredients at 40%, 50%, 60%, 70%, and 80% ethanol concentrations. Repeat the measurement three times for each group to obtain five sets of data, and then draw a graph to obtain the optimal ethanol concentration level range.

[0068] (4) Material-liquid ratio: Weigh 0.5 g of Cinnamomum camphora, fix the microwave temperature at 60°C, the microwave time at 12 min, and the ethanol concentration at 60%, and take material-liquid ratios of 1:12, 1:16, 1:20, 1:24, and 1:28, respectively, to extract the active ingredients. Repeat the measurement three times for each group to obtain five sets of data, and draw a graph to obtain the optimal material-liquid ratio level range.

[0069] 1.2.2.3 Optimization of ultrasonic extraction process conditions by response surface analysis

[0070] Table 3 Factors and levels of Box-Behnken experimental design

[0071]

[0072] 1.2.2.4 Optimization of ultrasonic extraction process conditions using response surface analysis

[0073] On the basis of the single-factor experiment, a four-factor three-level experiment was designed with ethanol concentration (A), microwave power (B), extraction time (C), and solid-liquid ratio (D) as experimental factors, as shown in Table 4. The total flavonoid extraction rate was used as the response value to determine the optimal extraction process.

[0074] Table 4 Factors and levels of Box-Behnken experimental design

[0075]

[0076] 2 Results and Analysis

[0077] 2.1 Ultrasound single factor test results and analysis

[0078] 2.1.1 Results and analysis of the effect of extraction time on the yield of total flavonoids from camphor leaves The solid-liquid ratio was fixed at 1:24, the ultrasonic power was 240W, and the ethanol concentration was 60%. The effects of different extraction times (10, 20, 30, 40, 50 min) on the yield of total flavonoids from camphor leaves were investigated. The results are shown in Figure 2 .

[0079] from Figure 2 It can be seen that extraction time has a significant effect on the total flavonoid yield of camphor leaves, showing a trend of first increasing and then decreasing. As the extraction time increases from 10 minutes to 30 minutes, the total flavonoid yield of camphor leaves shows a slow upward trend. This is because as the extraction time increases, the contact time between the solvent and the flavonoids in the camphor leaves is prolonged, allowing more flavonoids to dissolve in the extraction solvent, thereby gradually increasing the total flavonoid yield. From 30 minutes to 40 minutes, the total flavonoid yield shows a significant jump, indicating that during this time period, the extraction process enters a high-efficiency stage, with flavonoids rapidly dissolving into the solvent. This may be because the early extraction process further disrupts the cell structure, allowing for more complete flavonoid release. When the extraction time is extended from 40 minutes to 50 minutes, the total flavonoid yield decreases significantly. This may be because the extraction time is too long, causing chemical reactions such as oxidation and decomposition of the flavonoids, or because some impurities are further dissolved, interfering with the extraction and determination of the flavonoids, resulting in a decrease in the total flavonoid yield. In general, in the extraction process of total flavonoids from Cinnamomum camphora leaves, the longer the extraction time is, the better. 40 minutes is a more suitable extraction time, which can make the yield of total flavonoids from Cinnamomum camphora leaves reach a relatively high level.

[0080] 2.1.2 Results and analysis of the effect of ultrasonic power on the yield of total flavonoids from Cinnamomum camphora leaves

[0081] The solid-liquid ratio was fixed at 1:24, the ultrasonic time was 40 min, and the ethanol concentration was 60%. The effects of different ultrasonic powers (160, 200, 240, 280, 320 W) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in Figure 3.

[0082] Figure 3 The effect of ultrasonic power on the total flavonoid yield from camphor leaves is shown. The figure clearly shows that the total flavonoid yield from camphor leaves increases first and then decreases with varying ultrasonic power. As the ultrasonic power gradually increases from 160W, the total flavonoid yield slowly increases. When the ultrasonic power reaches 240W, the total flavonoid yield reaches a peak. This is because, within a certain range, increasing ultrasonic power can enhance the cavitation effect of ultrasound. The instantaneous collapse of tiny bubbles produced by cavitation creates a localized high-temperature and high-pressure environment. This environment helps to destroy the cell walls of camphor leaf cells, facilitating the release of the total flavonoids within the cells into the extraction solvent, thereby increasing the total flavonoid yield. Above 240W, the total flavonoid yield begins to decline. At ultrasonic powers of 280W and 320W, the total flavonoid yield is significantly lower than the peak. This may be because excessively high ultrasonic power leads to excessively high local temperatures, which trigger chemical reactions such as oxidation and decomposition of the total flavonoids, thereby reducing the effective extraction yield. At the same time, excessive ultrasonic power may also cause excessive volatilization of the solvent, resulting in an unstable extraction system and affecting the extraction efficiency of total flavonoids. In summary, ultrasonic power has a significant effect on the yield of total flavonoids from Cinnamomum camphora leaves. Under the experimental conditions, an ultrasonic power of 240W is more suitable for the extraction of total flavonoids from Cinnamomum camphora leaves, and can achieve a relatively high yield.

[0083] 2.1.3 Results and analysis of the effect of ethanol concentration on the yield of total flavonoids from Cinnamomum camphora leaves

[0084] The solid-liquid ratio was fixed at 1:24, the ultrasonic time was 40 min, and the ultrasonic power was 240 W. The effects of different ethanol concentrations (40, 50, 60, 70, 80%) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in Figure 4 .

[0085] Figure 4The effect of ethanol concentration on the total flavonoid yield from Cinnamomum camphora leaves is presented. As shown in the figure, the total flavonoid yield from Cinnamomum camphora leaves shows a trend of first increasing and then decreasing with changes in ethanol concentration. The total flavonoid yield gradually increases as the ethanol concentration increases from 40% to 60%. This is because flavonoid compounds have certain solubility characteristics. Within this concentration range, as the ethanol concentration increases, their solubility for the total flavonoids in Cinnamomum camphora leaves increases, enabling more efficient extraction of the total flavonoids from the leaf tissue. However, as the ethanol concentration continues to increase from 60% to 80%, the total flavonoid yield decreases significantly. This may be because excessively high ethanol concentrations cause other components in the Cinnamomum camphora leaves (such as fat-soluble impurities) to dissolve in large quantities. These impurities compete with the total flavonoids for solubility and may interfere with the extraction and subsequent analysis of the total flavonoids, resulting in a decrease in the total flavonoid yield. In summary, ethanol concentration significantly affects the total flavonoid yield from Cinnamomum camphora leaves. Under the conditions of this experiment, an ethanol concentration of 60% is more suitable for extracting total flavonoids from Cinnamomum camphora leaves, achieving a high total flavonoid yield.

[0086] 2.1.4 Results and analysis of the effect of solid-liquid ratio on the yield of total flavonoids from camphora leaves

[0087] The ultrasonic time was fixed at 40 min, the ultrasonic power was 240 W, and the ethanol concentration was 60%. The effects of different solid-liquid ratios (1:16, 1:20, 1:24, 1:28, 1:32) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in the figure. Figure 5 .

[0088] Figure 5 The effect of different material-liquid ratios on the yield of total flavonoids from camphor leaves was demonstrated. When the material-liquid ratio changed from 1:16 to 1:24, the yield of total flavonoids from camphor leaves showed a downward trend. This may be because the material-liquid ratio was too small, that is, the amount of solvent used was relatively small, which could not fully soak the camphor leaf raw material, resulting in the total flavonoids in the leaves not being fully dissolved in the solvent, thereby reducing the extraction efficiency. When the material-liquid ratio increased from 1:24 to 1:28, the yield of total flavonoids increased significantly. This is because as the amount of solvent used increased, it was able to better contact and dissolve the total flavonoids in the camphor leaves, allowing more total flavonoids to be extracted. However, when the material-liquid ratio continued to increase to 1:32, the yield of total flavonoids decreased again. This may be because too much solvent would dilute the concentration of total flavonoids in the solution and may also cause some impurities to dissolve more, thereby affecting the extraction purity and yield of total flavonoids. In summary, under the conditions set in this experiment, the yield of total flavonoids from camphor leaves was relatively high when the material-liquid ratio was 1:28, which is a more suitable material-liquid ratio condition.

[0089] 2.2 Microwave single factor test results and analysis

[0090] 2.2.1 Results and analysis of the effect of extraction time on the yield of total flavonoids from Cinnamomum camphora leaves

[0091] The solid-liquid ratio was fixed at 1:20, the microwave power was 500W, and the ethanol concentration was 60%. The effects of different extraction times (4, 8, 12, 16, 20 min) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in Table 2. Figure 6 .

[0092] Figure 6 The effects of different extraction times on the yield of total flavonoids from camphor leaves were presented. As the extraction time increased from 4 min to 8 min, the yield of total flavonoids from camphor leaves increased significantly. This is because as the extraction time increased, microwave energy had more time to act on the camphor leaves, causing the cell structure to be gradually destroyed, and the total flavonoids in the leaves were more easily dissolved into the ethanol solvent. When the extraction time increased from 8 min to 12 min, the yield of total flavonoids decreased slightly. This may be because during this period, some of the dissolved total flavonoids decomposed or reacted with other substances, resulting in a slight decrease in the yield. When the extraction time was extended from 12 min to 16 min, the yield of total flavonoids increased significantly, indicating that at this stage, the continuous action of microwaves further destroyed the cell structure, allowing more total flavonoids to be released, and at the same time, the factors that may have previously inhibited the dissolution of total flavonoids were also reduced. However, when the extraction time continued to increase from 16 min to 20 min, the total flavonoid yield decreased significantly. This is probably because the extraction time was too long, and the total flavonoids underwent oxidation and decomposition under the combined action of microwaves and ethanol, which reduced the yield. In summary, under the conditions set in this experiment, the extraction time had a significant effect on the total flavonoid yield of Cinnamomum camphora leaves. The extraction time of 16 min was more suitable and could obtain a relatively high total flavonoid yield.

[0093] 2.2.2 Results and analysis of the effect of microwave power on the yield of total flavonoids from Cinnamomum camphora leaves

[0094] The effects of different microwave powers (300, 400, 500, 600, 700W) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated with a fixed material-liquid ratio of 1:20, extraction time of 12 min, and ethanol concentration of 60%. Figure 7 .

[0095] from Figure 7As can be seen, the yield of total flavonoids from Cinnamomum camphora leaves shows a trend of first decreasing, then increasing, and then decreasing again with changes in microwave power. When the microwave power increases from 300 W to 400 W, the flavonoid yield decreases. This may be because, within this power range, excessive microwave power causes certain components in the Cinnamomum camphora leaves to overreact or be destroyed, affecting the extraction efficiency of flavonoids. As the microwave power increases from 400 W to 600 W, the flavonoid yield gradually increases, reaching a maximum at 600 W. This indicates that increasing microwave power within this power range is beneficial for the extraction of total flavonoids from Cinnamomum camphora leaves, likely because appropriate microwave power enhances molecular motion and promotes the diffusion of flavonoids from plant tissue into the extraction solvent. When the microwave power is further increased from 600 W to 700 W, this may be due to thermal effects or other side reactions caused by excessive microwave power, which destroy flavonoids and further reduce the yield. In summary, a microwave power of 600 W is optimal for the extraction of total flavonoids from Cinnamomum camphora leaves. At this power, the yield of total flavonoids from Cinnamomum camphora leaves is the highest.

[0096] 2.2.3 Results and analysis of the effect of ethanol concentration on the yield of total flavonoids from Cinnamomum camphora leaves

[0097] The material-liquid ratio was fixed at 1:20, the microwave time was 12 min, and the microwave power was 500 W. The effects of different ethanol concentrations (40, 50, 60, 70, 80%) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in Table 2. Figure 8 .

[0098] Figure 8 The effect of ethanol concentration on the yield of total flavonoids from camphor leaves is shown. As can be seen from the figure, as the ethanol concentration changes, the yield of total flavonoids from camphor leaves shows a trend of first increasing and then decreasing. When the ethanol concentration increases from 40% to 50%, the yield of total flavonoids increases. This is because flavonoid compounds have a certain solubility. Within this concentration range, as the ethanol concentration increases, their solubility of total flavonoids in camphor leaves increases, and total flavonoids can be more effectively extracted from leaf tissue. When the ethanol concentration continues to increase from 50% to 80%, the yield of total flavonoids gradually decreases. This may be because excessively high ethanol concentration causes other components in camphor leaves (such as fat-soluble impurities) to dissolve in large quantities. These impurities compete with total flavonoids for solubility space and may interfere with the extraction and subsequent determination of total flavonoids, resulting in a decrease in the yield of total flavonoids. In summary, under the conditions of this experiment, an ethanol concentration of 50% is more suitable for the extraction of total flavonoids from camphor leaves, and a relatively high yield can be obtained.

[0099] 2.2.4 Results and analysis of the effect of material-liquid ratio on the yield of total flavonoids from Cinnamomum camphora leaves

[0100] The microwave time was fixed at 12 min, the microwave power was 500 W, and the ethanol concentration was 60%. The effects of different material-liquid ratios (1:12, 1:16, 1:20, 1:24, 1:28) on the yield of total flavonoids from Cinnamomum camphora leaves were investigated. The results are shown in the table. Figure 9 .

[0101] Figure 9 The effect of the solid-liquid ratio on the yield of total flavonoids from camphor leaves was demonstrated. In the experimental setting, other conditions were fixed, and only the solid-liquid ratio was changed to observe the change in the yield of total flavonoids. When the solid-liquid ratio increased from 12 to 20, the yield of total flavonoids from camphor leaves showed an upward trend. This is because as the amount of solvent used relative to the amount of raw materials increased, the solvent was able to more fully infiltrate the camphor leaves, fully contact and dissolve the total flavonoids in the leaves, thereby improving the extraction efficiency of total flavonoids. However, when the solid-liquid ratio continued to increase from 20 to 28, the yield of total flavonoids showed a downward trend. This may be because the solid-liquid ratio is too large. Excessive solvent will dilute the concentration of total flavonoids in the solution, and it may also cause more impurities to dissolve, interfering with the extraction and determination of total flavonoids, thereby reducing the yield. In summary, under the conditions of this experiment, when the solid-liquid ratio is 20, the yield of total flavonoids from camphor leaves is relatively high, which is a more suitable solid-liquid ratio parameter.

[0102] 2.3 Results and analysis of ultrasonic response surface optimization process conditions

[0103] 2.3.1 Establishment of regression model for total flavonoids yield from Cinnamomum camphora leaves

[0104] Based on the single-factor experiment, a four-factor, three-level response surface analysis experiment was designed, with four influencing factors as independent variables and the total flavonoids yield from camphor leaves as the dependent variable. Using Design Expert 10.0.1, the data obtained from the experiment were regressed and fitted to obtain a regression equation. The surface of the equation and its projected line were analyzed and discussed in a three-dimensional coordinate plot, allowing for intuitive visualization of the optimal condition region and its projection. The results of the Design Expert 10.0.1 analysis are shown in Table 5 below.

[0105] Table 5 Box-Behnken experimental design and data results

[0106]

[0107]

[0108] After regression fitting of the experimental data, the quadratic polynomial regression equation of the total flavonoids yield (Y) of Cinnamomum camphora leaves and the coding values ​​of ultrasonic power (A), extraction time (B), solid-liquid ratio (C), and ethanol concentration (D) was obtained:

[0109] Y=8.48-0.0164A+0.0585B+0.1860C-0.5557D-0.0185AB+0.2256AC-0.1515AD+0.0924BC+0.5808BD-0.0336CD-0.2291A 2 -0.2077B 2 -0.1922C 2 -0.4570D 2 .

[0110] 2.3.2 Response surface data processing and analysis of total flavonoids extraction from Cinnamomum camphora leaves

[0111] 2.3.2.1 Significance test of total flavonoids extraction rate from Cinnamomum camphora leaves

[0112] The results of the significance test of each coefficient of the regression model and the analysis of equation variance are shown in Table 6.

[0113] As shown in Table 6, the P value of the model is 0.1563, which is greater than the significance level of 0.05, indicating that the regression model is not significant overall. This means that the combination of factors selected by the model may not be able to explain the changes in the total flavonoid yield of Cinnamomum camphora leaves well. The model may have defects, or the selected factors are not the key factors affecting the total flavonoid yield. Further optimization of the model or re-screening of factors is needed. 2 =0.6348, indicating that the model explains 63.48% of the variation in total flavonoid yield, indicating that the model fit is average. 2 adj =0.2696, and R 2The large gap indicates that there may be some irrelevant independent variables in the model, which reduces the reliability of the model. Ultrasonic power (A): The P value is 0.9195, which is much greater than 0.05, indicating that the effect of ultrasonic power on the total flavonoids yield of Cinnamomum camphora leaves is not significant. That is, changing the ultrasonic power, under the conditions of this experiment, has no obvious effect on increasing or decreasing the total flavonoids yield. Ultrasonic time (B): The P value is 0.7197, which is greater than 0.05, indicating that the effect of ultrasonic time on the total flavonoids yield is not significant and is not a key factor affecting the total flavonoids extraction effect. Solid-liquid ratio (C): The P value is 0.2634, which is greater than 0.05, indicating that the solid-liquid ratio has no significant effect on the total flavonoids yield within the range of this experiment. Ethanol concentration (D): The P value is 0.0037, which is less than 0.01, indicating that the effect of ethanol concentration on the total flavonoids yield of Cinnamomum camphora leaves is extremely significant. This shows that among the experimental factors, ethanol concentration is the key factor affecting the total flavonoids yield, and changes in its concentration will significantly affect the extraction effect of total flavonoids. The P values ​​for most interaction terms were greater than 0.05, indicating that the interaction between these factors had no significant effect on the total flavonoid yield. Only the P value for the BD interaction term was 0.0543, close to the significance level of 0.05, suggesting that the interaction between ultrasonic time and ethanol concentration may have a certain effect on the total flavonoid yield, but further verification is needed. The P value for the lack-of-fit error was 0.7146, greater than 0.05, indicating that the lack-of-fit error was not significant, that is, the experimental data fit the model well, and there were no significant factors not captured by the model that affected the total flavonoid yield. The pure error reflects the random error of the experiment, with a mean square value of 0.3945. Compared with the residual mean square (0.3058), it shows that the random error in the experimental process is within an acceptable range.

[0114] Table 6 Analysis of variance of response surface test results

[0115]

[0116]

[0117] Note: *. Significant difference (P<0.05); **. Extremely significant difference (P<0.01).

[0118] 2.3.2.2 Optimization and analysis of response surface for total flavonoids extraction from Cinnamomum camphora leaves

[0119] Regression fitting was performed using Design Expert 10.0.1 software to obtain a regression equation to predict the effects of four factors on ketone yield, such as Figure 10 The contour map and response surface map can intuitively reflect the degree of influence of the interaction on the response value. The denser the contour lines and the steeper the surface, the more significant the influence.

[0120] like Figure 10As shown in the figure, the surface shows a trend of first rising and then falling. Within a certain range, with the increase of ultrasonic power and ultrasonic time, the yield of flavonoids from camphor leaves gradually increases. After reaching a peak, the flavonoid yield begins to decrease when the ultrasonic power and ultrasonic time are further increased. This shows that in the process of ultrasonic-assisted extraction of flavonoids from camphor leaves, there is an optimal combination range of ultrasonic power and ultrasonic time, within which a higher flavonoid yield can be obtained. As can be seen from the figure, the contour lines are relatively dense in some areas, which means that in these areas, slight changes in ultrasonic power and ultrasonic time will cause significant changes in flavonoid yield.

[0121] Figure 11 The effect of the interaction between ultrasonic power and solid-liquid ratio on the yield of flavonoids from Cinnamomum camphora leaves is demonstrated. The three-dimensional surface plot shows a trend that initially rises and then flattens. Within a certain range, the yield of flavonoids from Cinnamomum camphora leaves gradually increases with increasing ultrasonic power and varying solid-liquid ratios. This suggests that within this range, increasing ultrasonic power helps improve the efficiency of solvent disruption of Cinnamomum camphora leaf cells and the dissolution of flavonoids, while a suitable solid-liquid ratio can provide a more favorable environment for flavonoid dissolution. The densely packed contour lines in the figure are elliptical in shape, indicating that the interaction between ultrasonic power and solid-liquid ratio has a significant effect on the extraction rate.

[0122] Figure 12 This study presents the interactive effect of ultrasound power and ethanol concentration on flavonoid yield from camphor leaves. A three-dimensional surface plot shows that flavonoid yield initially increases and then decreases with changes in ultrasound power and ethanol concentration. Areas with dense isobars in the figure indicate a significant interaction between the two factors on flavonoid yield.

[0123] like Figure 13 As shown in the figure, the flavonoid yield first increased and then decreased; the contour lines were sparse, indicating that the changes in ultrasonic time and material-liquid ratio had little effect on the flavonoid yield, and the interaction between extraction time (B) and material-liquid ratio (C) was not significant.

[0124] Figure 14 This study presents the interactive effect of ultrasound time and ethanol concentration on flavonoid yield from Cinnamomum camphora leaves. Flavonoid yield initially increased and then decreased with increasing ultrasound time and ethanol concentration. Contour lines were densely packed in some areas, indicating a significant interaction between ultrasound time and ethanol concentration. Overall, the interaction was not significant.

[0125] Figure 15 This study presents the interactive effects of the solid-liquid ratio and ethanol concentration on the flavonoid yield from Cinnamomum camphora leaves. Flavonoid yield initially increases and then decreases with increasing solid-liquid ratio and ethanol concentration. The sparse contour lines indicate a nonsignificant interaction between ultrasonication time and ethanol concentration.

[0126] 2.4 Results and analysis of microwave response surface optimization process conditions

[0127] 2.4.1 Establishment of regression model for total flavonoids yield from Cinnamomum camphora leaves

[0128] Based on the single-factor experiment, a four-factor, three-level response surface analysis experiment was designed, with four influencing factors as independent variables and the total flavonoids yield of Cinnamomum camphora leaves as the dependent variable. Using Design Expert 10.0.1, we performed a regression fit on the experimental data to obtain a regression equation. The surface of the equation and its projected line were analyzed and discussed in a three-dimensional coordinate plot, allowing for intuitive visualization of the optimal condition region and its projection. The results, analyzed using Design Expert 10.0.1 software, are shown in Table 7.

[0129] Table 7 Box-Behnken experimental design and data results

[0130]

[0131]

[0132] After regression fitting of the experimental data, the quadratic polynomial regression equation of the total flavonoids yield (Y) of Aquilaria sinensis leaves and the coded values ​​of ethanol concentration (A), microwave power (B), ethanol concentration (C), and solid-liquid ratio (D) was obtained:

[0133] Y=7.49-0.2417A-0.3153B+0.0460C+0.1802D+0.2421AB-0.2451AC-0.1324AD+0.0265BC-0.1862BD-0.6002CD+0.1279A 2 +0.0866B 2 +0.0094C 2 -0.0188D 2 .

[0134] 2.4.2 Response surface data processing and analysis of total flavonoids extraction from Cinnamomum camphora leaves

[0135] 2.4.2.1 Significance test of total flavonoids extraction rate from Cinnamomum camphora leaves

[0136] The results of the significance test of each coefficient of the regression model and the analysis of equation variance are shown in Table 8.

[0137] As shown in Table 8, the model P = 0.3472 (> 0.05), not significant; R 2 =0.5533, goodness of fit, R 2 adj=0.1066, indicating the presence of irrelevant variables requiring optimization. Microwave power (B): P = 0.0521 (marginally significant), indicating a potential impact on flavonoid yield. CD interaction (microwave time × material-liquid ratio): P = 0.0351, indicating a significant synergistic effect between the two, necessitating analysis of their combined effects. Other factors (A, C, D) and their interactions (AB, AC, AD, BC, BD) were not significant (P > 0.05). The lack-of-fit error (P = 0.1485) indicated a good fit between the experimental data and the model, and the random error (pure error) was controllable. Focusing on the interaction between microwave power and material-liquid ratio (CD), we re-screened key factors. Microwave power was nearly significant, and the interaction between material-liquid ratio and microwave time was significant, suggesting a significant synergistic effect between the two factors on flavonoid yield. Adjusting the combination of these two factors could improve extraction efficiency and provide guidance for process optimization.

[0138] Table 8 Analysis of variance of response surface test results

[0139]

[0140]

[0141] Note: *. Significant difference (P<0.05); **. Extremely significant difference (P<0.01).

[0142] 2.4.2.2 Optimization and analysis of response surface for total flavonoids extraction from Cinnamomum camphora leaves

[0143] Regression fitting was performed using Design Expert 10.0.1 software to obtain a regression equation to predict the effects of four factors on ketone yield, such as Figure 16-21 The contour map and response surface map can intuitively reflect the degree of influence of the interaction on the response value. The denser the contour lines and the steeper the surface, the more significant the influence.

[0144] Figure 16 The three-dimensional surface in the figure illustrates the changes in flavonoid yield (Z-axis) as a function of the interaction between ethanol concentration (X-axis) and microwave power (Y-axis). The flavonoid yield shows a continuous upward trend with increasing ethanol concentration and microwave power, indicating that the two factors synergistically enhance flavonoid dissolution. There is no decrease in yield due to excessively high parameters. The surface is smooth and lacks a clear inflection point, indicating that within the experimental parameter range, the interaction primarily promotes dissolution, without triggering negative effects such as flavonoid decomposition or excessive impurity dissolution. The contour lines are evenly distributed, indicating that the yield responds relatively stably to changes in both. In summary, the interaction between ethanol concentration and microwave power promotes flavonoid dissolution.

[0145] Figure 17This study presents the dynamic changes in flavonoid yield from Cinnamomum camphora leaves as a function of the interaction between ethanol concentration and microwave time. Flavonoid yield initially increases and then decreases with increasing ethanol concentration and prolonged microwave time. Contour lines are densely packed in the peak region, reflecting an interaction; contour lines are sparse in the peripheral regions, indicating a weak interaction. In summary, the interaction between ethanol concentration and microwave time is not significant.

[0146] Figure 18 The results show the changes in flavonoid yield as a function of the interaction between ethanol concentration and material-to-liquid ratio. The results show that flavonoid yield decreases with increasing ethanol concentration, while the material-to-liquid ratio does not change significantly. Furthermore, the contour lines are densely packed in the peak region and sparsely packed in the edge region. There is no significant interaction between ethanol concentration and material-to-liquid ratio.

[0147] Figure 19 The results show the effect of microwave power and time on flavonoid yield. The results show that flavonoid yield increases linearly with increasing microwave power and time, with no decrease. This indicates that increasing microwave power and time synergistically promote flavonoid dissolution without triggering flavonoid degradation, demonstrating stability within the parameter range. The contour lines are sparsely parallel, indicating a weak interaction.

[0148] Figure 20 The three-dimensional surface in the figure shows the change in flavonoid yield (Z-axis) as a result of the interaction between microwave power (X-axis) and material-to-liquid ratio (Y-axis). It can be seen that the flavonoid yield shows a continuous upward trend with increasing ethanol concentration and microwave power, indicating that the two factors synergistically enhance flavonoid dissolution. The response surface is smooth and has no obvious inflection points, indicating that within the experimental parameter range, the interaction between the two factors primarily promotes dissolution, without triggering negative effects such as flavonoid decomposition or excessive dissolution of impurities. The contour lines are evenly distributed, indicating that the yield responds relatively stably to changes in both factors. In summary, the interaction between microwave power and material-to-liquid ratio promotes flavonoid dissolution, but the interaction is not significant.

[0149] like Figure 21 The interaction analysis between microwave time and material-liquid ratio showed that the flavonoid yield first increased and then stabilized in the peak area, indicating that both factors affected the yield through a synergistic effect. The dense contour lines in some areas indicated that there was a significant interaction between ultrasound time and material-liquid ratio. In summary, the interaction between microwave time and material-liquid ratio was significant.

[0150] As can be seen from the above examples, the present invention uses response surface optimization methodology to conduct a series of studies on the ultrasonic and microwave extraction of total flavonoids from Cinnamomum camphora leaves. By analyzing the experimental data and establishing a response surface model, the optimal extraction conditions were obtained:

[0151] (1) Ultrasonic method: Within the experimental range, as the extraction time prolonged, the flavonoid yield increased slowly, then increased significantly, and then decreased; as the ultrasonic power increased, the total flavonoid yield of Cinnamomum camphora leaves first increased and then decreased; as the ethanol concentration increased, the flavonoid yield first increased and then decreased; as the material-liquid ratio increased, the flavonoid yield first decreased, then increased significantly, and then decreased.

[0152] (2) Microwave method: Within the experimental range, as the extraction time prolonged, the flavonoid yield first increased, then decreased, then increased significantly, and then decreased significantly; as the ultrasonic power increased, the total flavonoid yield of Cinnamomum camphora leaves showed a trend of first decreasing, then increasing, and then decreasing; as the ethanol concentration increased, the flavonoid yield first increased and then decreased; as the material-liquid ratio increased, the flavonoid yield first increased and then decreased.

[0153] (3) In the variance analysis of the response surface experiment using ultrasound, ethanol concentration had a highly significant effect on the total flavonoid content of Cinnamomum camphora leaves. The order of factors affecting the total flavonoid yield of Cinnamomum camphora leaves was: ethanol concentration > solid-liquid ratio > ultrasound time > ultrasound power. The P value of the interaction term between ultrasound time and ethanol concentration was 0.0543, close to the significance level of 0.05, suggesting that the interaction between ultrasound time and ethanol concentration may have a certain effect on the total flavonoid yield.

[0154] (4) In the variance analysis of the response surface experiment using microwave method, microwave power (B) had a potential effect on flavonoid yield: P = 0.0521 (marginally significant). CD interaction (microwave time × material-liquid ratio): P = 0.0351, indicating a significant synergistic effect between the two. The order of factors affecting the total flavonoid yield of Cinnamomum camphora leaves was: microwave power > ethanol concentration > material-liquid ratio > microwave time.

[0155] (5) Through response surface optimization analysis, the optimal ultrasonic extraction process was determined to be: extraction time 30 min, solid-liquid ratio 1:32 (g / mL), ethanol concentration 50%, and ultrasonic power 280 W. Under these conditions, the total flavonoids extraction yield reached 8.979%. The optimal microwave process conditions for total flavonoids extraction from Cinnamomum camphora leaves were: extraction time 18 min, solid-liquid ratio 1:23 (g / mL), ethanol concentration 57%, and microwave power 543 W. Under these conditions, the total flavonoids extraction yield reached 7.375%. The ultrasonic method had a higher extraction rate than the microwave method, with a total flavonoid content of 0.0449 mg / mL.

[0156] In summary, the present invention optimizes the optimal process of ultrasonic extraction and microwave extraction of Cinnamomum camphora leaves, provides a reference for the efficient extraction of total flavonoids from Cinnamomum camphora leaves, and provides a basis for the comprehensive utilization of Aquilaria sinensis leaf resources.

[0157] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. It is apparent to those skilled in the art that various changes, modifications, substitutions, and variations of these embodiments may be made without departing from the principles and spirit of the present invention, and the changes still fall within the scope of protection of the present invention.

Claims

1. A method for extracting total flavonoids from camphora leaves based on ultrasonic method, characterized in that: The dried powder of camphor tree leaves is added to an ethanol solution with a volume concentration of 50-70% at a material-liquid ratio of 1 g: 24-32 mL, and then placed in an ultrasonic instrument for ultrasonic extraction at an ultrasonic power of 220-270 W for 30-40 minutes. After extraction, solid impurities are removed and the filtrate is collected to obtain the product.

2. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, wherein The material-liquid ratio is 1g:32mL.

3. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, wherein The volume concentration of the ethanol solution is 50%.

4. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, wherein The ultrasonic power of ultrasonic extraction was 280W.

5. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, characterized in that: The ultrasonic extraction time was 30 min.

6. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, characterized in that: The Cinnamomum camphora leaf dry powder is Cinnamomum camphora leaf residue dry powder.

7. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, characterized in that: The size of the camphor leaf dry powder is 50-100 meshes.

8. The method for extracting total flavonoids from camphor tree leaves based on ultrasonic method according to claim 1, characterized in that: After collecting the filtrate, a drying step is also included.

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